The conservative Judicial Crisis Network is using the Supreme Court fight to attack Sens. Joe Manchin and Heidi Heitkamp, two centrist Democrats up for reelection in 2018, even as it backs GOP incumbent Sens. Kelly Ayotte and Chuck Grassley, the Senate Judiciary chairman.The ads, first shared with POLITICO, make up $1.5 million of JCN's initial $2 million ad buy set to run over the two-week congressional recess. Another TV spot will be launched next week against Sen. Michael Bennet of Colorado, the most vulnerable Democratic incumbent. More ads will debut on digital media and radio, sources said.It's all part of a unified campaign by right-leaning activist groups intended to help insulate Republicans from Democratic criticism of their plans to deny Merrick Garland's confirmation. The attack ads are intended to hurt Manchin and Heitkamp in their conservative home states. The ad against North Dakota's Heitkamp, for example, says that the Supreme Court's makeup "will preserve or end" the state's way of life on issues like energy production and "religious freedom."

"President Obama wants to add another liberal Supreme Court justice. A justice that will weaken the right to bear arms, hurt the coal industry and trample the Constitution. Tell Joe Manchin that he should let the people decide and not allow Obama to stack the court with liberal judges," says a narrator in the West Virginia ad, alongside a photo of Manchin with President Barack Obama.

In the ads meant to buttress Ayotte in New Hampshire and Grassley in Iowa, the ominous music of the attack ads is replaced by a hopeful soundtrack and fawning praise. The Iowa ad beckons voters to "stand with Sen. Grassley and keep a president in his last days from installing a new liberal majority on the Supreme Court." The longtime GOP senator drew a serious Democratic opponent this month.

"Sen. Kelly Ayotte believes in being thoughtful and protecting the Constitution, especially when it comes to the Supreme Court," the New Hampshire ad says. "President Obama wants to rush through another liberal nominee. Kelly Ayotte disagrees. She believes the people of New Hampshire should have a voice in this nomination. Stand with. Sen. Ayotte."

Ayotte is fighting a closely contested race with Democratic Gov. Maggie Hassan, and liberal groups are planning to engage her in events in New Hampshire.

While the ads will provide significant cover for Republicans, Democrats are fighting on a different front, mobilizing liberal groups and Democratic activists to try and shame GOP senators into changing their positions while they are back home on recess.

So conservatives are working their own ground game. With the Republican National Committee, America Rising and JCN handling research and advertising, groups like SBA List and Tea Party Patriots will be working on state-based activism with letters to the editor and messages of support to Grassley.

The idea is to blunt the effectiveness of liberal protesters disrupting senators' events back home by showing that the GOP is united around Senate Majority Leader Mitch McConnell's Supreme Court position even as Republicans are painfully divided about the presidential race.

"We are going to showup at town hall meetings," said Jenny Beth Martin, co-founder of Tea Party Patriots. "We're going to focus primarily on Republicans ... then shift to Democrats ... this is what the 2014 election was all about."